The event-based computation paradigm has grown in importance for enterprises. For example, many business applications and system control applications can be developed based on event-based computation. Generally, event processing applications receive events, analyze the events, and output results (e.g., proposed actions) based on the analysis of the events.
Current event processing systems often use structured query language (SQL) queries to analyze events. Due to the fluid nature of event streams, the relational algebra underlying traditional SQL may not be well-suited for processing events at a high rate. Additionally, performing time-based calculations using the relational operators provided by SQL may be difficult. Further, the semantics of a SQL query may require recitation of specific data sources, rendering a particular SQL query that recites a particular data source unsuitable for use with a different data source.